OF PEDICULARIA AND OTHER FORMS. 243 



posterior part bearing no operculum. The margin of the mantle, as in Jasonilla, was 

 rather thick ; and a pectinate gill extended along the dorsal region. The mouth was armed 

 on each side with a beautifully set pavement of sharp-pointed labial teeth ; and the liagual 

 ribbon, supporting 7 series of members, exhibited the closest relationship to that of 

 Myponyx and Pileopsis. Finally, single spherical otolithes were apparent through the 

 transpai-ent pedicle of the foot. Here is an incontrovertible case of a young oceanic 

 Gasteroi^od still undergoing development, but manifesting every essential anatomical 

 character present in Macgillicraia and Cheletropis, which we have hitherto regarded as 

 perfect forms. 



EXPLANATION OF THE PLATE. 

 Tab. XLII. 



Fig. 1. Little cancellated pelagic shell, closely resembling the minute spire of Pedicularia. 



Figs. 2 &3. Enlarged back and front views of the same. 



Fig. 4. Small portion of the shell, more highly magnified to show its characteristic sculpturing agreeing 



with that of Pedicularia. 

 Fig. 5. The operculum. 



Fig. 6. One transverse row of the lingual ribbon. 

 Fig. 7- A species of Pedicularia brought up from a depth of 40 fathoms, on a small Madrepore, 1 mile and 



a half off Elizabeth Reef. Lat. 29° 55' 27" S., Long. 159° 2' 54" E. (The natural size is seen 



to the left.) 

 Fig. H. One transverse row of the lingual teeth of the same, for comparison with fig. 6, which is not so 



fully developed, but in other particulars very similar. 

 Fig. 9. Enlarged figures of a minute pelagic Gasteropod, having six ciliated arms and a clawed operculum, 



allied to a species previously figured and described. 

 Fig. 9 a. Portion of mantle with ciliated bands and processes, more highly magnified. 

 Fig. 10. Three-quarter view of the same shell. 

 Fig. 11. Lateral labial teeth. 



Fig. 12. Lateral view of small pelagic Gasteropod enclosed in a stout cartilaginous case. 

 Fig. 13. Front view of the same. 



Fig. 14. The animal removed from the outer case and slightly twisted in its rudimentary shell. 

 Fig. 15. The auditory capsule. 

 Fig. 16. Lateral labial teeth. 

 Fig. 17. Portion of lingual ribbon. 



VOL. XXII. 2 K 



